Page:Popular Science Monthly Volume 38.djvu/479

Rh "simply a jacket" of boiler iron lined with, fire-brick. It was fifty feet high and twelve feet "bosh."

The make of iron was twenty tons in twenty-four hours. Since the date of the erection of this furnace, which at the time was the only blast-furnace in Alleghany County (in which Pittsburg is situated), Pennsylvania, there have been built within its territory twenty-four coke furnaces, which produced in 1889 "more pig iron than the whole State of Ohio; more than twice as much as Illinois; and more than one seventh of the country's total production."

The furnaces have not only increased in number, but their size and output have been very much augmented. As an illustration of this, furnace "F," of the "Edgar Thomson Steel Works," is eighty feet high, twenty-two feet diameter at the "boshes," eleven feet diameter of hearth, sixteen feet in diameter at the throat, and has a capacity of 18,000 cubic feet. This furnace produces 10,603 gross tons of iron per month (351 tons per day) on a fuel consumption of 1,756 pounds (coke) per gross ton. The pressure of blast at the tuyères is nine pounds per square inch, and its volume 25,000 cubic feet per minute, heated to 1,200° Fahrenheit.

While the iron-masters west of the Alleghany Mountains were increasing the number, size, and economical working of their furnaces, the makers of "anthracite iron" in the Lehigh, Schuylkill, and Susquehanna Valleys were by no means idle; and their furnaces also increased in size and multiplied in number as the years passed. As illustrating the influence of a successful manufacture in drawing population and other industries to its immediate vicinity, no better instance could be selected than the town of Catasauqua, Pennsylvania, where was built in 1840 the furnace described in the first part of this article. Where then was but a single furnace, a small number of scattered houses, and a few score of people, we now find five furnaces, two rolling-mills, and a number of collateral industrial establishments, giving sustenance to a large and busy population. Fig. 40 is a view of the present blast-furnace plant at Catasauqua. For the purpose of showing